Based on the data provided, we can observe that the coin in question has had a starting price in the current auction of 30 euros, with a conservation grade of 70 (MBC-). Additionally, it has been auctioned in the past on several occasions, with varying starting and final prices.

The average starting price of this coin in previous auctions has been 71.19 euros, while the average final price has been 92.35 euros. Regarding the previous prices of this coin, we can see that it has had fluctuations in its starting, estimated, and final values over the years.

Considering the historical data from previous auctions and the current starting price, as well as the conservation grade of the coin, we can estimate a maximum purchase price for this coin in the current auction. Given that the average final price has been 92.35 euros and the conservation grade of the coin is 70 (MBC-), we could consider a maximum estimated purchase price around 100-110 euros.

It is important to note that the final auction price may vary depending on the demand at that specific moment, so it is advisable to monitor the auction's progress to adjust the offer accordingly.